Comparison of Three Different Schedules of Measles Vaccination in Infants: a Pilot Randomized Controlled Trial
试验速览
- 阶段
- 不适用
- 发起方
- 入组人数
- 120
- 试验地点
- 1
- 主要终点
- Proportion of protected infants from measles.
研究概览
简要总结
Measles is a preventable infectious viral disease. Since 1985, India has been administering a single dose of measles vaccine to all infants at 9 months of age. This age was chosen to balance the disappearance of maternal (transplacental) antibodies with the increasing risk of developing measles. Thus infants are expected to get protection against measles by acquired maternal measles antibodies derived trans-placentally from the mother for the first 9 months of life. Thereafter vaccine-induced antibodies are expected to protect infants. Seroconversion after measles vaccination does not take place as long as maternal measles antibodies persist in the infant. However, it is widely recognized that a substantial proportion of measles infection (10 to 15%) can occur among infants before the age of measles vaccination. Further, two small cohort studies done in our institution confirm that the majority of infants lose maternal antibodies by six months of age, making them susceptible to measles.This argues strongly for anticipating measles vaccination to an earlier age. However, such early vaccination has the risk that residual maternal antibodies (even if insufficient to protect infants) can neutralize the antigen in the vaccine, rendering vaccination ineffective. Therefore, a careful balance has to be chosen so that low levels of circulating maternal antibodies do not interfere with infants' response to vaccination. However, there is no prospective study in Indian infants to determine the seroconversion and sero-protection rate of earlier vaccination.
This study has following aims and objectives:
- To study the level of measles specific immunoglobulin G (IgG) antibodies in a cohort of term infants followed from birth to 9 months of age; and the pattern of antibody decline in them.
- To compare the levels of antibodies in infants at these time points and correlate the levels with the antibody level in the respective mothers at the time of delivery.
- To compare the efficacy and safety of three different measles vaccination schedules in a cohort of term infants viz (i) vaccination at 9 months of age (current practice), (ii) vaccination at 7.5 months and 9 months of age, and (iii) vaccination at 6 months and 9 months of age.
详细描述
Study design:
This study has two design components viz.
- Prospective enrollment of a cohort of term infants at birth; and 3 monthly follow-up at the ages of 3 months, 6 months, 9 months and 12 months.
- Randomization at 6 months of age to three intervention groups viz (i) measles vaccination at 9 months of age (as per current practice), (ii) vaccination at 7.5 months and 9 months of age, and (iii) vaccination at 6 months and 9 months of age.
Methods: Enrollment:
Pregnant women awaiting delivery in the Department of Obstetrics and Gynecology will be screened for eligibility (as per the Inclusion and Exclusion criteria). Women whose infants are likely to be eligible for participation in the study will be explained about the nature and purpose of the study prior to delivery. They will be informed about the study protocol and invited to participate. After delivery, mothers and their respective newborn babies, will be enrolled with written, informed consent.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Double (Participant, Outcomes Assessor)
盲法说明
The participants are infants ranging from 6-9 months of age. They are expected to be unaware of the intervention. The laboratory personnel performing the antibody level measurements will be blinded by sending the samples with only a four digit code that does not reveal the intervention received.
入排标准
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Infants born at term (i.e.> 37 completed weeks of gestation) within the hospital will be eligible for inclusion into the study.
排除标准
- •Infants born to mothers known to have known immunodeficiency determined through examination of clinical records (HIV positive and those on immunosuppressive therapy during pregnancy).
- •Babies born with antenatally or postnatally diagnosed congenital anomalies that are anticipated to be life-threatening.
研究组 & 干预措施
GROUP A
measles vaccine at 6 months and 9 months of age
干预措施: Measles vaccine (Biological)
GROUP C
measles vaccine at 9 months of age (current practice)
干预措施: Measles vaccine (Biological)
GROUP B
measles vaccine at 7.5 months and 9 months of age
干预措施: Measles vaccine (Biological)
结局指标
主要结局
Proportion of protected infants from measles.
时间窗: 6 weeks after vaccination
Infants with serum anti measles IgG antibody levels higher than 200 m IU/ml, or other specific values provided by manufacturers in the antibody kits, will be taken as protected.
次要结局
- Infant- Mother antibody correlation at birth(At birth)
- Infant- Mother antibody correlation at 6 months(At 6 months of age)
- Acute measles(Birth to 12 months of age)
- Infant- Mother antibody correlation at 3 months(At 3 months of age)
- Susceptibility among vaccinated infants(Birth to 12 months of age)
- Incidence of treatment - emergent adverse events(3 days after vaccination)
- Susceptibility among not vaccinated infants(Birth to 12 months of age)
研究者
MAKAM LAXMI GOPAL
JUNIOR RESIDENT, DEPARTMENT OF PEADIATRICS
Post Graduate Institute of Medical Education and Research, Chandigarh